EXPERIMENTAL INVESTIGATION OF DAILY COLD ACCUMULATION BY WATER USE OF UNDERGROUND HORIZONS IN KIEV
The results of an experimental study of the effectiveness of the use of a daily cold water battery for the production of serial fan coil in order to provide air conditioning in a separate room are presented.
The in-situ experimental unit contains a production well, an absorption well, storage tanks, a flowmeter, a cold water thermometer, an indoor air thermometer, a network pump, a waste water thermometer, a cooling room, and a fan coil.
Water with a temperature of 12°C from the production well is fed by a downhole pump to a group of storage tanks, which are a battery of cold. After the water has accumulated in the tanks, a network pump is switched on, which supplies water from the storage tanks to the fan coils. The water that passed through the fan coils and cooled the room enters the absorption well.
The purpose of the experiment is to investigate the cold water storage system as a daily accumulation of cold water and its subsequent use to provide comfortable indoor conditions with the help of serial fan coil.
The main characteristics of the experiment: the flow rate of water at the outlet of the well is 0.9 kg/s, the flow rate of water entering the fancoil - 0.1 kg/s, the flow rate of air through the fancoil - 340 m3/h, the flowing water temperature to the storage tank - 12°С, the temperature of the water entering the fan coil - 12,5°С, the cooling area of the room - 20 m2, the initial temperature in the room - 28ºС, the number of storage tanks - 7 pcs., the total volume of the storage tanks - 7 m3.
As a result of the experiments, the room temperature was reduced to 23°C for 3 hours of fancoil operation. The cooling capacity of the fan coil was found to vary from 3640 watts in the initial period to 1820 watts at the end of the cooling process. The temperatures of the coolant at the outlet of the fan coil were 21.5°C and 17.1°C, respectively.
Studies have shown that the water storage system of underground horizons with an initial water temperature of 12°C works effectively in the cooling mode of the room using serial fan coils. Heat storage tanks in the form of storage tanks are also effectively used as buffer tanks for regulating the supply of water to the fan coils. Accumulation of solid sediments is observed in the storage tanks when the water is stored for more than 2 days. The discrepancy between the calculated values of the temperature and the experimental values does not exceed 5-7%. The system needs further upgrading to automatically measure water parameters and room temperature and humidity. Ref. 13, fig. 7.
2. Inayat A., Raza M. District cooling system via renewable energy sources: A review. Renewable and Sustainable Energy Reviews. June. 2019. V. 107. Pp. 360-373. [in English].
3. Ampofo F., Maidment G.G., Missenden J.F. Review of groundwater cooling systems in London. Applied Thermal Engineering. 2006. V. 26. Pp. 2055-2062. [in English].
4. Kuo C., Liao H. The feasibility of using circulating groundwater as renewable energy sources for air-conditioning in Taipei basin. Renewable Energy. 2012. V. 39. Pp. 175-182. [in English].
5. Morozov Yu.P. Dobycha geotermalnykh resursov i akku-mulirovaniye teploty v podzemnykh gorizontakh. [Extraction of geothermal resources and accumulation of heat in underground horizons]. Kyiv. Naukova Dumka. 2017. 198 p. [in Ukrainian].
6. Morozov Yu.P., Velychko V.V., Kushnir I.O. Otsinka teplovoho potentsialu verkhnikh shariv Zemli na terytorii Ukrainy. [Estimation of thermal potential of the upper Earth's layers in Ukraine]. Vidnovluvana energetika. 2018. No. 4(55). Pp. 84-92. [in Ukrainian].
7. Velychko V.V. Okholodzhennia povitria v prymishchenni v litnii period za dopomohoiu fankoilu ta vertykalnoi sverdlovyny. [Cooling indoor air in the summer through fan coil and vertical borehole]. Materials XVII international conference Renewa-ble energy and energy efficiency of the XXI century. 2016. Pр. 486-489. [in Ukrainian].
8. Nesterenko A.V. Osnovyi termodinamicheskih raschetov ventilyatsii i konditsionirovaniya vozduha. [Fundamentals of thermodynamic calculations of ventilation and air conditioning]. М. Vyisshaya shkola. 1971. 459 p. [in Russian].
8. Rivkin S.L., Aleksandrov A.A. Termodinamicheskie svoystva vodyi i vodyanogo para. [Thermodynamic properties of water and water vapor]. M. Energoatomizdat. 1984. 80 p. [in Russian].
9. Syichev V.V., Vasserman A.A., Kozlov A.D. i dr. Ter-modinamicheskie svoystva vozduha. [Thermodynamic properties of air]. M. Izdatelstvo standartov. 1978. 276 p. [in Russian].
10. Sniezhkin Yu.F., Chalaiev D.M., Dabizha N.O. Analiz enerhetychnykh pokaznykiv protsesu teplonasosnoho sushinnia. [Analysis of energy performance of the process of heat pump drying]. Promyslova teplotekhnika. 2017. V. 39. No. 3. Pp. 47-52. [in Ukrainian].
11. Galayda L. Potolochnoe ohlazhdenie pomescheniya kak alternativa konditsionirovaniyu. [Room ceiling cooling as an alternative to air conditioning]. AWTherm. 2018. No. 2. Pp. 82-86. [in Russian].
Abstract views: 41 PDF Downloads: 29